JP6237090B2 - Peening processing equipment - Google Patents

Description

  The present invention relates to a peening apparatus for applying a shock to a surface of a metal material with a vibrating pin to improve the structure, shape, and the like of a surface portion of the metal material.

  In the present invention, the mechanical vibration is a mechanical vibration of 50 Hz or more caused by a mechanical system, and is defined to include a case of ultrasonic vibration as a typical example.

  Steel structures, especially steel bridges, have been several decades after construction, and ships have been in service for several years, such as welds of steel members of structures and notches formed in steel members. The occurrence of cracks due to fatigue is a problem.

  Further, in construction machines and the like, the occurrence of fatigue cracks in booms that are exposed to shocking repeated loads during use is a problem. In automobiles, fatigue cracks may be a problem in chassis, drive shafts, and the like.

  In this way, when constructing structures and equipment using steel members, the design thickness of the member, welding form, etc. are designed in consideration of degradation of material performance due to fatigue and degradation of welded portion performance, etc. doing.

  Recently, by subjecting the surface of the material to ultrasonic peening, plastic deformation is applied to the surface of the material to impart compressive residual stress, thereby improving the crystal structure of the surface or releasing the residual stress. It is known that fatigue performance can be improved. For example, Patent Document 1 proposes a method for setting processing conditions when modifying the surface layer of a metal material.

  In addition, by applying ultrasonic peening treatment to the welded part or notch, etc., compressive residual stress is applied while releasing the tensile residual stress due to welding, and the structure of the peened part is improved. Research has been conducted to improve the fatigue resistance of these parts by reducing the stress concentration by improving the shape of the material to a shape having a curvature.

  As such an ultrasonic peening apparatus, Patent Document 2 discloses an apparatus for changing a vibration direction of a pin by mounting a waveguide having a tilt angle and a pin holder corresponding to the waveguide on the tip of the casing. The tip structure is described. However, in the method of Patent Document 2, the inclination angle of the striking pin is 20 to 45 degrees, so it cannot be used in a wide area such as a narrow part.

  Patent Document 3 describes an ultrasonic shock treatment apparatus in which the waveguide itself resonates and can be bent up to 120 degrees. However. In the method of Patent Document 3, the shape of the waveguide is fixed and it is difficult to adjust the angle, and it is difficult to manufacture a resonating waveguide.

JP 2004-169099 A JP 2006-055799 A JP-T 2009-504397

  FIG. 1 is a schematic diagram showing an outline of an ultrasonic peening apparatus described in Patent Document 2 described above. In general, since the ultrasonic peening apparatus is relatively small, it can be processed manually and has an advantage that only a required part can be processed. In the ultrasonic peening apparatus described in Patent Document 2, as shown in FIG. 1, the axial direction of the striking pin 3 has an inclination angle with respect to the vibration direction of the wave guide. According to this processing apparatus, it is difficult to change the angle of the processing apparatus main body in order to obtain an appropriate angle in the axial direction of the pin with respect to the toe of the weld metal 3 that is the processing target. Processing "can be performed.

  However, when the inclination angle of the hitting pin 3 is increased, the attenuation rate of the vibration energy is rapidly increased and the processing efficiency is lowered. Therefore, the inclination angle is limited to 20 to 45 degrees. Therefore, the present invention can be used in a wide range of parts such as narrow parts by efficiently and easily realizing vibration direction conversion at a large angle compared to the prior art, and can be processed even if the inclination angle of the hitting pin is increased. It is an object of the present invention to provide a peening processing apparatus in which efficiency does not decrease.

The present invention has been made to solve the above-described problems, and the gist thereof is as follows.
(1) A wave guide that guides mechanical vibration generated by the mechanical vibration generator forward and a plurality of pins that are excited by the mechanical vibration and shock-vibrated are connected in series to transmit the shock-vibration to the workpiece. A peening processing apparatus having a group and a pin holder provided with a guide hole for holding the pin group so as to vibrate in the pin axis direction, wherein the plurality of pins are connected to each other by point contact at an end portion. And the peening apparatus characterized by the fact that the vibration directions of the connecting portions are inclined at an angle α.
(2) The wave guide and the pin are connected to each other by point contact, and the perpendicular of the wave guide surface at the connecting portion and the pin axis direction are inclined at an angle β. The peening processing apparatus according to (1).

(3) The wave guide is characterized in that the surface in contact with the pin is inclined at an angle γ of 40 degrees or less, preferably 30 degrees or less, with the perpendicular of the surface and the axis of the wave guide. The peening processing apparatus according to (1) or (2).
(4) The plurality of pins and the connection portions between the pins and the wave guide are 5 or less, and the inclination angle of the vibration direction at one connection portion is α ≦ 30 ° in the case of the pins, and the pin and the wave guide. In this case, β ≦ 40 °, preferably β ≦ 30 °, the peening apparatus according to any one of (1) to (3).
(5) The peening apparatus according to any one of (1) to (4), wherein the guide hole includes a one-side through hole provided in the pin holder.

(6) The pin holder is an insert member having a guide hole for holding the pin so as to be able to vibrate, wherein one or a plurality of serial connection portions of the plurality of pins are divided by a cross section of the vibration propagation path The peening apparatus according to any one of (1) to (4), wherein a plurality of inserted insert members are incorporated.
(7) The guide hole is formed by providing a pin groove including a recess into which a pin is inserted into the pin holder divided in a longitudinal section of a vibration propagation path. The peening processing apparatus according to any one of 4).
(8) The peening processing apparatus according to any one of (1) to (7), wherein the pin group has a plurality of systems, and processing at a plurality of locations is possible at the same time.
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According to the invention of (1), the plurality of pins that are subjected to shock vibration are connected to each other by point contact at the end portions, and the vibration directions of the pins are gradually inclined at an angle α at the connection portion. Therefore, even if the total of the tilt angles becomes large, the damping rate of the impact vibration at the tip can be suppressed rather than changing the angle greatly at one time as in the prior art.
According to the invention of (2), the wave guide and the pin are connected to each other by point contact, and the perpendicular of the wave guide surface at this connecting portion and the pin axis direction are inclined at an angle β. Therefore, the vibration direction can be easily inclined.

According to the invention of (3), since the surface in contact with the pin is inclined at an angle γ of 40 degrees or less, preferably 30 degrees or less, with the perpendicular of the surface and the axis of the wave guide, the impact vibration Can be suppressed.
According to the invention of (4), a plurality of pins and connecting portions between the pins and the wave guide are 5 or less, and when the inclination angle of the vibration direction at one connecting portion is between pins, α ≦ 30 °, In the case of the pin and the wave guide, by setting β ≦ 40 °, preferably β ≦ 30 °, the damping rate of the impact vibration can be suppressed to 30% or less even if the total inclination angle is 140 degrees.
According to the invention of (5), since the guide hole is composed of only one side through hole provided in the pin holder, it is not necessary to divide the pin holder, and it is not necessary to connect each part as in the split type.・ It becomes easy to reduce the size.

According to the invention of (6), the pin holder is an insert member having a guide hole for holding the pin so as to be able to vibrate, wherein one or a plurality of serially connected portions of the plurality of pins is a vibration propagation path. Since it has a structure in which a plurality of insert members divided in the cross section are built-in, the guide holder can be processed with high accuracy for each divided insert member, and the manufacture of the pin holder is easy.
According to the invention of (7), the guide hole is formed by providing a pin groove formed by a concave portion into which the pin is inserted into the pin holder divided by the longitudinal section of the vibration propagation path. Even when the number of times is large, the guide hole can be easily formed from one divided surface. In addition, handling is easy because all the pins can be attached and exchanged at one time with the pin holder divided.
According to the invention of (8), since there are a plurality of pin groups, a plurality of locations can be processed simultaneously.

  According to the peening processing apparatus of the present invention, it is possible to use in a wide range of parts such as a narrow part by easily realizing a vibration direction change of a larger angle than before, and even if the inclination angle of the hitting pin is increased It is possible to provide a peening treatment apparatus in which efficiency does not decrease, and there are significant industrially useful effects.

It is a schematic diagram which shows the outline | summary of the conventional peening processing apparatus. It is a schematic diagram which shows the outline | summary of the peening processing apparatus of this invention. It is a figure which illustrates 1st Embodiment of the peening processing apparatus of this invention. It is a figure which illustrates 2nd Embodiment of the peening processing apparatus of this invention. It is a figure which illustrates 3rd Embodiment of the peening processing apparatus of this invention. It is a figure which shows the influence of the inclination angle in the vibration direction change location, and the frequency | count of direction change which has on the effect in the surface of the vibration attenuation factor of the peening processing apparatus of this invention. It is a figure which shows the influence of the combination of the inclination angle in a vibration direction change location, and the sum total of a direction change angle which has on the effect in the surface of the vibration attenuation factor of the peening processing apparatus of this invention.

  Hereinafter, the present invention will be described in detail with reference to FIGS. 2 to 5, 1 is a pin holder, 2 is a striking pin, 2 'is a waveguide pin, 3 is a weld metal, 4 is a wave guide, 5 is a pin holder base, 6 is a one-side through hole, and 7 is an insert member. , 8 are pin grooves, and α, β, and γ are inclination angles.

  FIG. 2 is a schematic diagram showing an outline of the peening apparatus of the present invention. As shown in FIG. 2, the peening apparatus according to the present invention includes a wave guide 4 that guides mechanical vibration generated by a mechanical vibration generator (not shown) to the front, and a plurality of pins that are excited by the mechanical vibration and shock-vibrated. Is a peening processing apparatus having a pin group that is connected in series and that transmits the impact vibration to a material to be processed, and a pin holder 1 that includes a guide hole that holds the pin group so as to vibrate in the pin axial direction. The plurality of pins are connected to each other at the end portions by point contact, and the vibration directions of the plurality of pins are inclined at the connection portions. The plurality of pins that undergo impact vibration are connected to each other by point contact at the end portions, and the vibration direction is inclined little by little at the connection portion, so even if the total inclination angle becomes large, Thus, the damping rate of the impact vibration at the tip can be suppressed rather than changing the angle greatly at one time.

  The internal structure of the pin holder 1 used in the present invention is shown in FIGS. A plurality of pins (striking pin 2 and guide pin) that receive mechanical vibration of 50 Hz or more, including a case of ultrasonic vibration in a typical example, which is generated by a mechanical vibration generator (not shown), and are excited by this mechanical vibration to perform impact vibration. The wave pin 2 ') is connected in series in the pin holder, and the impact vibration is propagated to the adjacent pin, and the weld metal 3 is hit with the hit pin 2 at the tip.

  The pin holder 1 has a guide hole having a function of holding a pin while enabling mechanical vibration of the pin with a diameter equivalent to that of the pin, and a structure in which an inclination angle is obtained by always making point contact between adjacent pins. . Further, since the wave guide 4 and the pin are connected to each other by point contact and the vibration direction is inclined, the vibration direction can be easily inclined. A combination of the connection between the pins having these inclination angles and the connection between the pins and the wave guides, for example, a plurality of pins connected from the body direction of the peening apparatus so that it can be applied to the weld metal 3 in the narrow portion. The vibration direction can be changed in an arbitrary direction up to the axial direction of the tip impact pin 2. In addition, the contact state of a pin can be confirmed by providing a window hole in the pin connection part in the pin holder 1.

Further, since the surface in contact with the pin is inclined at an angle of 40 degrees or less between the perpendicular of the surface and the axis of the wave guide 4, the damping rate of the impact vibration can be suppressed. If the angle exceeds 40 degrees, the angle difference between the vibration direction of the surface and the vibration direction of the pin becomes too large, and the component force other than the vibration direction of the pin increases the frictional force at the time of vibration of the pin and inhibits smooth vibration. Become. 30 degrees or less is desirable in order to advantageously reduce the influence of component forces other than the vibration direction of the pin.
Furthermore, by providing a plurality of pin groups, a plurality of locations can be processed simultaneously.

  The peening processing apparatus basically includes a mechanical vibration generator (not shown), a wave guide 4, a hitting pin 2, a waveguide pin 2 ', and a pin holder 1 that holds the pin. In FIG. 2, the striking pin 2 side is referred to as the front, and the mechanical vibration generator side is referred to as the rear.

  For example, in the case of vibration with a high frequency, the mechanical vibration generator is composed of a magnetostrictive body such as permendur and a coil wound around the magnetostrictive body, and generates axial ultrasonic vibration by electric energy from a power source. To occur. There is also a method of changing an electrical signal into mechanical vibration by a piezoelectric element. In the case of vibration with a low frequency, there are various hammer mechanisms in which the tip tool vibrates in the axial direction by air pressure or electric power, and this can also be used. An inclined surface having an inclination angle with respect to the direction of the main body axis is formed at the distal end portion of the wave guide.

  The pin holder 1 is provided with a guide hole for supporting the striking pin 2 and the waveguide pin 2 '. The guide hole is provided so that its axis is in the same direction as the direction of the axis of the striking pin. That is, the axis of the guide hole is provided so as to have an inclination angle with respect to the direction of the main body axis, and thereby the axis of the hitting pin 2 has an inclination angle with respect to the main body axis. In addition, it is preferable to provide the retainer which consists of an elastic material which prevents dropping of a pin in the edge part of a guide hole, and hold | maintains a pin.

  The pins (striking pin 2 and waveguide pin 2 ') are usually made of a material excellent in characteristics such as wear resistance, hardness, and toughness, such as a cemented carbide. In the present invention, the shape of the pin is not limited, but a straight rod shape is preferable because it is easy to manufacture. The shape of the tip is not particularly defined, but is usually a convex shape with a curvature. Depending on the shape of the processing portion, the hitting end on the front side of the hitting pin may have a concave tip shape. The cross-sectional shape perpendicular to the axis of the pin is not limited to a circle, and may be an ellipse or a plane according to the application. Furthermore, when the pin shape is a plate shape having a width, the contact between the pins may be a line contact.

  The mechanical vibration in the axial direction generated by the mechanical vibration generator by the electrical energy from the power source is amplified and propagated to the wave guide 4 in front of the vibration propagation direction to mechanically vibrate the front inclined surface. This mechanical vibration is transmitted to the pin group (waveguide pin and striking pin) in contact with the inclined surface, and is excited by this mechanical vibration to cause shock vibration at random. As a result, the peening target object in front thereof, for example, a welded part or notch part of a metal structure is hit, imparts compressive residual stress, reforms the metal surface structure, and residual stress of the welded part. The effect of reducing or releasing can be given.

  Hereinafter, the embodiment of the peening apparatus according to the present invention shown in FIGS. 3 to 5 will be described more specifically. FIG. 3 is a diagram illustrating the first embodiment of the peening apparatus according to the present invention. Since the guide hole is composed of a one-side through hole 6 provided in the pin holder 1, it is not necessary to divide the pin holder 1, and it is not necessary to connect each part as in the split type. Can be made thin and compact. In this case, as shown in FIG. 3, the one-side through-holes 6 are preferably the same as the number of pins, and at least one-side through-holes inclined to each other are easily manufactured.

  The striking pin 2 and the waveguide pin 2 ′ are inserted and held in the guide hole formed by the one-side through hole 6, and the end of the pin is brought into point contact so that the vibration direction of the wave guide 4 indicated by the arrow is γ. , Β, α2, α1, and the impact vibration can be transmitted to the workpiece while being sequentially inclined. Note that. The inclination angles α (α1, α2,...), Β, and γ in the vibration direction are not limited to the inclination angles in the same plane, and the degree of freedom in the inclination direction can be increased by setting the inclination angles in different planes. .

  FIG. 4 is a diagram illustrating a second embodiment of the peening apparatus according to the present invention. The pin holder 1 is an insert member having a guide hole for holding a group of pins so as to be able to vibrate, and one or a plurality of serial connection portions of the plurality of pins are divided by a cross section of a vibration propagation path. Since it has a structure in which a plurality of insert members 7 are built in, it is easy to manufacture a pin holder such that a guide hole can be processed with high precision for each divided insert member. In this case, as shown in FIG. 4, the insert member 7 is provided with through holes that are inclined to each other in the same number as the number of pins. The striking pin 2 and the waveguide pin 2 ′ are inserted and held in this through hole, and the ends of the pins are brought into point contact so that the vibration direction of the wave guide 4 indicated by the arrows is sequentially γ, β, α2, α1. The striking vibration can be transmitted to the workpiece while being inclined. Note that. The inclination angles α (α1, α2,...), Β, and γ in the vibration direction are not limited to the inclination angles in the same plane, and the degree of freedom in the inclination direction can be increased by setting the inclination angles in different planes. .

  FIG. 5 is a diagram illustrating a third embodiment of the peening apparatus according to the present invention. The guide hole is formed by providing a pin groove 8 formed of a recess into which a group of pins are inserted in a split surface of the pin holder divided by a longitudinal section of a vibration propagation path, so that the number of changes in the vibration direction is large. Even in this case, the guide hole can be easily formed from one dividing surface. In addition, handling is easy because all the pins can be attached and exchanged at one time with the pin holder divided. In this case, as shown in FIG. 5, the pin grooves 8 are formed by recesses inclined with respect to each other in the same number as the number of pins. The striking pin 2 and the waveguide pin 2 'are inserted and held in the pin groove 8, and the ends of the pins are brought into point contact so that the vibration direction of the wave guide 4 indicated by arrows is γ, β, α2, and α1. The striking vibration can be transmitted to the material to be processed while being sequentially inclined.

  When the peening process of the weld metal 3 was performed using the peening apparatus of the embodiment shown in FIGS. 2 and 3, the displacement in the vibration direction of the pin was attenuated with the change of direction. In other words, if the rotation is rotated by an angle θ in one connection, the striking ability will be cos θ times and the peening treatment ability will be reduced, and the attenuation due to the frictional force generated by the pin in the pin holder can also be considered. Is required. Attenuation curves assuming the inclination angle and the number of connections are calculated and shown in FIGS. 6 and 7 are the results of calculation assuming that the impact performance is cos θ times the inclination angle θ, and the influence of the frictional force is ignored.

  FIG. 6 shows the number of connections for each inclination angle of the pin (0 to 45 degrees) and the damping rate of the hitting ability. As the tilt angle increases, the attenuation rate increases. For example, when the sum of the tilt angles is 90 degrees, the attenuation rate reaches about 40% at 30 degrees × 3 times, but the attenuation rate is about 40% at 10 degrees × 9 times. It is suppressed to 10%. Thus, the greater the inclination angle, the greater the attenuation factor with increasing number of connections.

  Since the attenuation rate changes due to an increase in the inclination angle and the number of connections, even if the total conversion angle is the same, the attenuation rate changes depending on the combination of pin holders, and an optimal angle combination is expected to exist. Is done. As an example, FIG. 7 shows the calculation results when a maximum of 10 pin holders with inclination angles of 10, 15, and 20 degrees are combined and when only a pin holder with an inclination angle of 20 degrees is used. When the total conversion angle is 140 degrees or less, the attenuation rate can be suppressed by a combination of pin holders having inclination angles of 10, 15, and 20 degrees.

As a result of hitting using the peening treatment apparatus of the present invention, it was confirmed that peening treatment can be performed by connecting a plurality of pins. Prototype pin holders, collecting measured data including damping due to friction force generated on pin holders and pins, pin dimensions and shapes, and multiple connections with adjacent pins bonded, and inside and outside of pin holders that freely change direction As a result of examining the structure, the number of connecting portions of the plurality of pins and the wave guide is 5 or less, and the inclination angle of the vibration direction at one connecting portion is α ≦ 30 °, β ≦ 40 ° (preferably 30). It was found that by setting γ ≦ 40 ° (preferably 30 ° or less), the damping rate of impact vibration can be suppressed to 30% or less even when the total inclination angle is 140 °. In addition, when the inclination angle α in the vibration direction at the connecting portion of one pin in the pin holder is less than 10 degrees, the adjacent guide holes overlap in the integrated pin holder as shown in FIG. It can be difficult to machine, and even with a pin holder as shown in Figs. 3-5, the number of connections required to incline to a predetermined angle increases, so the structure becomes complicated and the maintenance becomes worse. It was.
In the case of an integral pin holder as shown in FIG. 3, if the tilt angle in the vibration direction is less than 10 degrees, the number of direction changes in the pin holder is limited to one from the point of pin hole processing.
In addition, when the tilt angle in the vibration direction is small in the integral pin holder, the part where the one side through holes partially overlap each other increases, so that the pin is sufficiently long to vibrate without shaking in the axial direction. It will be necessary.

DESCRIPTION OF SYMBOLS 1 Pin holder 2 Blow pin 2 'Wave guide pin 3 Weld metal 4 Wave guide 5 Pin holder base 6 One side through-hole 7 Insert member 8 Pin groove alpha, beta, gamma Inclination angle

Claims (8)

A wave guide for guiding the mechanical vibration generated by the mechanical vibration generating device forward, and a plurality of pins that are excited by the mechanical vibration and shock-vibrated are connected in series, and a group of pins that transmit the shock vibration to the workpiece; A pin holder with a guide hole that holds the pin group so as to vibrate in the axial direction of the pin, wherein the plurality of pins are inserted into the guide hole at the end. A peening apparatus characterized in that they are connected to each other by point contact, and their vibration directions are inclined at an angle α at the connecting portion.   The wave guide and the pin are connected to each other by point contact, and the perpendicular of the wave guide surface at the connecting portion and the pin axis direction are inclined at an angle β, The peening processing apparatus according to claim 1.   3. The peening according to claim 1, wherein the surface of the wave guide that is in contact with the pin is inclined at an angle γ of 40 degrees or less between the perpendicular of the surface and the axis of the wave guide. 4. Processing equipment.   The number of connecting portions between the plurality of pins and between the pins and the wave guide is 5 or less, and the inclination angle of the vibration direction at one connecting portion is α ≦ 30 ° in the case of the pins, and in the case of the pin and the wave guide The peening processing apparatus according to claim 1, wherein β ≦ 40 °.   5. The peening apparatus according to claim 1, wherein the guide hole includes a one-side through hole provided in the pin holder.   The pin holder is an insert member having a guide hole for holding a pin so as to vibrate, wherein one or a plurality of serial connection portions of the plurality of pins are divided by a cross section of a vibration propagation path. The peening apparatus according to any one of claims 1 to 4, wherein the insert member is incorporated.   The said guide hole is formed by providing the pin groove | channel which consists of a recessed part which inserts a pin in the said pin holder divided | segmented by the longitudinal cross-section of the vibration propagation path, The one of Claims 1-4 characterized by the above-mentioned. The peening apparatus according to item 1. The peening processing apparatus according to any one of claims 1 to 7, wherein the pin group has a plurality of systems, and processing at a plurality of locations is possible at the same time.

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